1. Field of the Invention
This invention relates to intrusion detection apparatus and, more particularly, to intrusion detector apparatus utilizing two detectors and appropriate arming and disarming elements and intrusion detector alarms.
2. Description of the Prior Art
U.S. Pat. No. 4,772,875 (Maddox et al) discloses a portable intrusion detector system utilizing two types of sensors. One sensor monitors a first condition, and a second sensor monitors a second condition. Both sensors must detect an intrusion before an intrusion status is transmitted.
U.S. Pat. No .4,833,450 (Buccola and Kolb) discloses an intrusion detection system utilizing a microwave system and a passive infrared subsystem. Both systems must produce an output signal indicative of an intrusion in order for the system to produce an alarm. The system also includes its own monitoring system for detecting faulty equipment or elements.
U.S. Pat. No. 4,710,750 (Johnson) discloses another dual sensor type of intrusion detection system. A passive infrared sensor is combined with a microwave sensor. A counter system is utilized by the apparatus. The counts of the two separate systems or detectors are compared for purposes of determining a fault in one of the two sensor systems. An intrusion must be detected by both systems in order for an alarm to be sounded.
U.S. Pat. No. 4,660,024 (McMaster) discloses a dual detection system, with both systems having to detect an intrusion before an alarm is provided. In addition, the apparatus includes malfunction or fault detecting apparatus. If a fault is detected in one of the systems, an alarm indicative of such is transmitted.
U.S. Pat. No. 4,625,199 (Pantus) discloses another type of dual system intrusion detection apparatus being ultrasonic and microwave detection subsystems. Both subsystems must detect an intrusion in order for an appropriate alarm to be transmitted.
U.S. Pat. No. 4,611,297 (Sansky) discloses a multiple sensor status monitoring system for monitoring the status of an area and for monitoring the sensing apparatus to detect and identify faulty sensors. An alarm system is transmitted or generated only if two sensors give a positive response to an intrusion within a predetermined time period. The apparatus includes latching elements to keep track of the spurious responses of the sensors, and to provide a visual display of the kept record.
U.S. Pat. No. 4,401,976 (Stadelmayr) discloses a multiple sensor system disposed at different locations and responsive to different physical phenomenon coupled together to provide an output when a majority of the sensors respond to a detected intrusion. Infrared sensors, microwave sensors, and ultrasonic sensors may each be utilized. That is, different types of sensors are utilized in the overall system.
U.S. Pat. No. 4,195,296 (Williams) discloses an intrusion detection system utilizing microwaves and the Doppler principle for detecting an intrusion.
U.S. Pat. No. 3,801,978 (Gershberg and Lee) discloses a dual detection system for detecting an intrusion utilizing an ultrasonic detector and a microwave detector, both of which must detect an intrusion in order for an alarm to sound.
U.S. Pat. No. 3,725,888 (Solomon) discloses a detector system utilizing a microwave detector and an optical detector. Again, both detectors must provide an output signal in order for an alarm signal to be produced.
U.S. Pat. No. 3,074,054 (Pearson) discloses a detection or intrusion system in which two different types of detectors are also used and an output signal from each of the systems is required in order to provide an intrusion output signal. An ultrasonic system and a microwave system are used in the apparatus.
U.S. Pat. No. 3,074,053 (McDonough et al) discloses another type of dual detector system for detecting intrusions. A photoelectric system and a capacitive system are utilized. Both systems must detect an intrusion before an alarm system is generated.
It will be noted that in the above-discussed patents, the circuitry involved is of paramount importance. Details of the activation and deactivation of the systems appear to be secondary. In several of the patents, the self-policing feature of detecting faults is also of primary importance. However, the practical application of the intrusion systems is not dealt with. Moreover, the intrusion detection systems are generally concerned with a broad spectrum of applications, such as detecting an intrusion in a predetermined area, such as a room, grounds, or the like. Of primary importance is the circuitry involved, with the particular space or area of secondary concern. In the apparatus of the present invention, two detector systems are utilized for confirmation purposes, but it is of primary importance to both provide a positive output signal when an intrusion is detected and to be able to selectively arm and disarm the intrusion detector system by a limited number of persons. That is, a child, for example, could not simply turn the system on or off to enable or to disable the system. Moreover, the apparatus is designed primarily for detecting intrusion, as by a child, in the area about a swimming pool so that an alert may be sounded before the child falls into the pool, as opposed to an alert after the child has already fallen into the pool.
The invention described and claimed herein comprises intrusion alert system utilizing two detectors, an infrared detector and a microwave detector, the outputs of which are coupled together to provide an output signal indicative of an intrusion when both systems detect such intrusion. The apparatus is enabled and disabled through a key pad system to provide that only the individuals knowing a particular code for the system can actually accomplish either the disabling or the enabling of the system. A pulse counter is utilized so that both detectors must confirm the intrusion within a predetermined period of time before an alarm sounds. Different types of alarms may be provided. An audible alarm, a visual alarm, and a telephonically transmitted alarm may each or all be utilized with the system.
Among the objects of the present invention are the following:
To provide new and useful intrusions detection apparatus utilizing infrared and microwave detectors;
To provide new and useful intrusion detection apparatus controlled by a coded key pad;
To provide new and useful intrusion detection apparatus utilizing two different types of detectors for confirming intrusion;
To provide new and useful intrusion detection apparatus having two detectors, each of which must provide an output signal within a predetermined time period confirming an intrusion in order to provide an output signal; and
To provide new and useful intrusion detection apparatus utilizing dual detectors and monitoring heat, movement, and mass for providing an output signal indicative of intrusion.